Date: Mon, 12 Mar 2012 22:11:28 +0200 From: Alexander Motin <mav@FreeBSD.org> To: Ivan Klymenko <fidaj@ukr.net> Cc: freebsd-performance@FreeBSD.org, FreeBSD current <freebsd-current@freebsd.org> Subject: Re: Improved Intel Turbo Boost status/control Message-ID: <4F5E5870.8000600@FreeBSD.org> In-Reply-To: <4f5e5730.aa4a440a.4367.ffffa591SMTPIN_ADDED@mx.google.com> References: <4F5E4B57.1050605@FreeBSD.org> <4f5e4f82.41972a0a.0e49.2cfdSMTPIN_ADDED@mx.google.com> <4F5E54A9.5050301@FreeBSD.org> <4f5e5730.aa4a440a.4367.ffffa591SMTPIN_ADDED@mx.google.com>
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On 03/12/12 22:05, Ivan Klymenko wrote: > В Mon, 12 Mar 2012 21:55:21 +0200 > Alexander Motin<mav@FreeBSD.org> пишет: > >> On 03/12/12 21:33, Ivan Klymenko wrote: >>> В Mon, 12 Mar 2012 21:15:35 +0200 >>> Alexander Motin<mav@FreeBSD.org> пишет: >>>> I'd like to note that recent r232793 change to cpufreq(4) in HEAD >>>> opened simple access to the Intel Turbo Boost status/control. I've >>>> found that at least two of my desktop systems (based Nehalem and >>>> SandyBridge Core i7s) with enabled Intel Turbo Boost in BIOS it is >>>> not use it by default, unless powerd is enabled. And before this >>>> change it was difficult to detect/fix. >>>> >>>> ACPI reports extra performance level with frequency 1MHz above the >>>> nominal to control Intel Turbo Boost operation. It is not a bug, >>>> but feature: >>>> dev.cpu.0.freq_levels: 2934/106000 2933/95000 2800/82000 ... >>>> In this case value 2933 means 2.93GHz, but 2934 means 3.2-3.6GHz. >>>> >>>> After boot with default settings I see: >>>> dev.cpu.0.freq: 2933 >>>> , that means Turbo Boost is disabled. >>>> >>>> Enabling powerd or just adding to rc.conf >>>> performance_cpu_freq="HIGH" >>>> enables Turbo Boost and adds extra 10-20% to the system >>>> performance. >>>> >>>> Turbo Boost operation can be monitored in run-time via the PMC with >>>> command that prints number or really executed cycles per CPU core: >>>> pmcstat -s unhalted-core-cycles -w 1 >>>> >>> >>> Thank you very much! >>> performance_cpu_freq="HIGH" >>> and as this option must be combined with state of the processor C1 >>> C2 C3? >>> performance_cx_lowest="XX" >>> economy_cx_lowest="XX" >> >> The more CPU cores on package are sleeping and the deeper they are >> sleeping, the bigger will be boost for remaining active cores. >> Without using deeper C-states boost is usually quite small (about >> 100-200MHz for desktop chips). Enabling C-states increases it in few >> times. >> > > I have a Core i5 c Turbo Boost technology (enabled in BIOS) > After the following: > sysctl dev.cpu.0.freq_levels > dev.cpu.0.freq_levels: 2301/35000 2300/35000 2000/29079 1800/25766 1600/22265 1400/18904 1225/16541 1200/15996 1050/13996 1000/12907 875/11293 800/9956 700/8711 600/7467 500/6222 400/4978 300/3733 200/2489 100/1244 > > performance_cpu_freq="HIGH">> /etc/rc.conf > > /etc/rc.d/powerd restart > > sysctl dev.cpu.0.freq_levels > dev.cpu.0.freq_levels: 2301/35000 2300/35000 2000/29079 1800/25766 1600/22265 1400/18904 1225/16541 1200/15996 1050/13996 1000/12907 875/11293 800/9956 700/8711 600/7467 500/6222 400/4978 300/3733 200/2489 100/1244 > > CPU frequency does not rise above 2300 Mhz > > What am I doing wrong? performance_cpu_freq variable handled not by /etc/rc.d/powerd, but /etc/rc.d/power_profile. -- Alexander Motin
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